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71.
Results of an experimental study of the shock–wave deformation of TiNi and its effect on the crystallographic structure and temperature of austenite–martensite transformations are given. It is found that, for pressures of up to 2 GPa, shock–wave loading changes the defect structure and parameters of the lattice; however, this does not lead to a noticeable change in the temperature of the austenite–martensite transformation and the manifestation of the shapeNdash;memory effect.  相似文献   
72.
A new tetraoxime ligand, (2E, 3E, 9E, 10E)-1, 4, 8, 11-tetraazacyclotetradecane-2, 3, 9, 10-tetrone tetraoxime has been prepared by the template condensation of 1,3-propanediamine and cyanogen-di-N-oxide, obtained by treating (E, E)-dichloroglyoxime in CH2Cl2 with Na2CO3 at −10 °C. The coordination chain polymers {[(pnngH2)2Ni]n (5) and [(pncgH2)2Cu]n(6)} of two transition metal ions, [Ni(II) and Cu(II)] with the vic-dioxime ligand have been prepared. The oxime ligand acts as a polydentate ligand bending through nitrogen atoms in the presence of a base, as do most of the vic-dioximes. In the complexes, the chloride ions coordinate to the nickel and copper ions. The structures of these novel vic-dioxime compounds are proposed on the basis of the elemental analyses, molar conductance data, i.r., and U.v.–visible are presented. Elemental analyses indicate a ligand metal ratio of 1:1 in the coordination polymers. Conductivity measurements have shown that mono- and polynuclear complexes are non-electrolytes. In addition, anti-microbial activities of the compounds have been investigated.  相似文献   
73.
In this paper, the differential geometry of second canonical extension2 M of a differentiable manifoldM is studied. Some vector fields tangent to2 M inTTM are determined. In addition we obtain that the second canonical extensions ofM and a totally geodesic submanifold inM are totally geodesic submanifolds inTTM and2 M respectively.  相似文献   
74.
In this article, the sub‐equation method is presented for finding the exact solutions of a nonlinear fractional partial differential equations. For this, the fractional complex transformation method has been used to convert fractional‐order partial differential equation to ordinary differential equation. The fractional derivatives are described in Jumarie's the modified Riemann–Liouville sense. We apply to this method for the nonlinear time fractional differential equations. With the aid of symbolic computation, a variety of exact solutions for them are obtained. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
75.
76.
A. A. Esin 《Mathematical Notes》2008,83(5-6):594-603
A classical theorem of Post [1] describes five precomplete classes in the set of Boolean functions. In [2], it was shown that there exist 18 precomplete classes of functions of three-valued logic. In [1, 2], the closure of sets of functions with respect to the substitution operator was studied. We consider two closure operators on functions of three-valued logic, which are obtained by supplementing the substitution operator by closures with respect to two identifications of function values, and prove the existence of three precomplete classes for one of these operators and five precomplete classes for the other.  相似文献   
77.
Summary. Unsymmetrical metal-free and metalo-porphyrazines (M=Mg, Zn, Co) made up of three phthalonitrile units and a single maleonitrile moiety on the periphery were prepared by cyclization of bis(2-dimethylaminoethylthio)maleonitrile and phthalonitrile. The magnesium derivative (Mgpz) was converted into the quaternized product by reaction with methyl iodide. The new compounds were characterized by elemental analysis, IR, NMR, mass, and electronic spectra.  相似文献   
78.
Summary.  Unsymmetric metallophthalocyanines (M=Zn, Co, Ni) carrying alkylthio and acetyloxyethylthio groups on peripheral positions were prepared from 4,5-bis-alkylthio-phthalonitrile, 4,5-bis-(acetyloxyethylthio)-phthalonitrile, and the corresponding anhydrous metal salts Zn(CH3COO)2, NiCl2, and CoCl2. The extremely soluble compounds were characterized by their IR, 1H NMR, and UV/Vis spectra. Their long wavelength absorption band was found to be bathochromically shifted; their solubility is superior to that of symmetrical phthalocyanines. Received July 27, 1999. Accepted (revised) September 30, 1999  相似文献   
79.
Measurement of total antioxidant activity/capacity of polyphenols in various solvent media necessitates the use of cyclodextrins to solubilize lipophilic antioxidants of poor aqueous solubility. The inclusion complexes of the slightly water soluble antioxidant, rosmarinic acid (RA), with α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), 2-hydroxyethyl-β-cyclodextrin (HE-β-CD), and methyl-β-cyclodextrin (M-β-CD) were investigated for the first time. The effect of cyclodextrins (CDs) on the spectral features of RA was measured in aqueous medium using UV-vis and steady-state fluorescence techniques by varying the concentrations of CDs. The molar stoichiometry of RA-CD inclusion complexes was verified as 1:1, and the formation constants of the complexes were determined from Benesi-Hildebrand equation using fluorescence spectroscopic data. Among the CDs, maximum inclusion ability was measured in the case of M-β-CD followed by HP-β-CD, HE-β-CD, β-CD and α-CD. Solid inclusion complexes were prepared by freeze drying, and their functional groups were analyzed by IR spectroscopy. Antioxidant capacity of CD-complexed rosmarinic acid was measured to be higher than that of the lone hydroxycinnamic acid by the CUPric Reducing Antioxidant Capacity (CUPRAC) method. The mechanism of the TAC increase was interpreted as the stabilization of the 1-e oxidized o-catechol moiety of RA by enhanced intramolecular H-bonding in a hydrophobic environment provided by CDs, mostly by M-β-CD.  相似文献   
80.
Journal of Solid State Electrochemistry - We managed to provide one-step facile electrochromic device (ECD) preparation to incorporate two cathodic coloring components into lithium ion (Li+)-doped...  相似文献   
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